Large displays are becoming more prevalent throughout society, from high-definition television to digital advertising applications. As the number of pixels in a display increases, the probability of producing a completely defect-free display typically drops. For most display applications, the current approach is to classify completed displays into quality categories based on the number of pixel and sub-pixel defects.
A consumer's discovery that a newly purchased display has ‘defects’ often leads to significant dissatisfaction. In advertising or public information applications, display defects may actually produce a negative impression in viewers of the display. In some critical industrial applications (e.g. medical imaging) defect-free displays are required to ensure accuracy of the information displayed or in other cases display defect locations can be visually flagged for display users. Consequently, this is a particularly challenging problem for display manufacturers.